The present invention relates generally to torque and/or rotational control apparatus such as clutches or brakes, and most particularly to replaceable pad mounting for clutches or brakes and to torque and/or rotational control apparatus having greatly increased heat dissipation.
It is a continuous problem to provide clutches or brakes which are efficient, have high ability to transfer the heat energy generated in the engagement process and/or in a constant slipping arrangement, and are easy to maintain and operate. U.S. Pat. No. 4,474,268 shows one type of apparatus designed to solve this problem and particularly is an external, multi-caliper brake arranged to provide controlled torque to a shaft including a hub arranged to be mounted to this shaft A longitudinally centrally located, internally finned friction disc is in turn mounted to the hub. The brake housing supports one or more brake cylinders or calipers, each of which in the most preferred form includes a fluid pressure actuated piston carrying a brake pad. The external calipers are fluid actuated to frictionally engage the friction disc and control the torque and/or rotation of the shaft. The multiplicity of calipers is for the intended purpose of broadening the range of torque and rotational control. It can then be appreciated that the capacity of the brake is dependent on the dissipation of heat which in turn is dependent upon air flow. The friction disc described provides increased cooling and increased brake efficiency by means of a finned arrangement. Specifically, the friction disc is formed of two, opposed, interlaced, finned portions to create a serpentine, radial and circumferential air cooling path for the friction disc and provide better heat transfer and increased brake efficiency. Although the apparatus of U.S. Pat. No. 4,474,268 showed a marked increase from prior apparatus in the ability to transfer the heat energy generated in the engagement process, further efforts were continued to improve capacity and efficiency including the utilization of cooling enhancing devices such as of the type taught in U.S. Pat. Nos. 4,561,522 and 4,846,315.
Thus, even with the development of apparatus having enhanced capabilities, the need and problem continue to provide apparatus with even greater ability to transfer the heat energy generated in the engagement process and/or in a constant slipping arrangement.
Similarly, although U.S. Pat. No. 4,474,268 shows a method for pad replacement that can be accomplished without the actual removal of any part of the apparatus to allow ease of maintenance, the need and problem continue to provide apparatus with even greater ease of pad replacement and without requiring the use of tools.